Key for lock anti-pick device

ABSTRACT

An anti-pick device for a lock is described in which a housing is mounted over the key slot entrance in the lock and a key holder is mounted slidably in the housing for movement along a path aligned with the key slot. A recess is provided in the key holder extending transversely of the path of movement of the key holder for receiving a key and supporting the key in alignment with the key slot.

United States Patent Wiczer May 13, 1975 [54] KEY FOR LOCK ANTI-PICKDEVICE 1,256,767 2/l9l8 Berg 70/447 1,768,040 6/1930 F h'ld... 70/408 X[761 Invent Max 9122 Kedvale- Skokle, 1,903,586 4/1933 Ai ri ld 70/408 X60652 3,334,501 8/1967 Greenwald... 70/423 [22] Filed: y 27, 19733,696,646 10/1972 Loscolzo 7()/l.5

[ PP N03 383,184 Primary Examiner-Robert L. Wolfe Related ApplicationData Attorney, Agent, or Firm-Fitch, Even, Tabin & [62] Division of Ser.No. 294,385. Oct. 2, 1973, Pat. No. Luedek [57] ABSTRACT [52] U.S. Cl70/406; 70/408 An ami pick device for a lock is described in which alift. i g i mounted Over the y slot entrance in the [58] Fleld 0f Search70/406, 407, 408, 419, lock and a y holder i mounted i y i the hous70/423 455 ing for movement along a path aligned with the key slot. Arecess is provided in the key holder extending [56] References C'tedtransversely of the path of movement of the key UNIT STATES PATENTSholder for receiving a key and supporting the key in 360,738 4/1887Smith 70/407 x alignment with the key slot. 582,367 5/1897 OKeefe..70/408 X 2 Cl 9 D F, 888,478 5/1908 Drew 70 407 x rawmg PATENIEB MAY 1 3I975 KEY FOR LOCK ANTI-PICK DEVICE This is a division of applicationSer. No. 294,385 filed Oct. 2, 1973, and now U.S. Pat. No. 3,765,199.

This invention relates generally to locking devices and, moreparticularly, to an anti-pick device for a lock having a key slot.

A common locking device in general use comprises a front flange, anelongated threaded body extending behind the flange, and a cylinderextending from the flange, within the body. A key slot in the lockprovides access to suitable internal devices which are operated by a keyinserted in the slot. This enables one to turn the cylinder and operatea cam or other suitable device actuated by turning the cylinder.Typically, the flange portion of the lock is the only portion thereofwhich is mounted, externally of the panel in which the lock is mounted,and a retainer nut is utilized threaded on the threaded body of the lockto securethe lock in place in the panel. The panel is thereby clampedbetween the nut and the front flange of the lock.

Various techniques have been devised by nefarious individuals withinsociety for opening such locks without the necessity of employing a key.Such techniques including picking, drilling, punching, and pulling thecylinder out of the lock.

In order to frustrate the activities of such persons employing theaforementioned techniques, various devices have been devised. Typicallythese prior art devices have not afforded as thorough protection againstillegal tampering as might be desired. Moreover, such prior art deviceshave often been difficult to install, expensive to construct, and havesometimes required modification of the lock itself.

It is an object of the present invention to provide an improvedanti-pick device for a lock having a key slot.

Another object of the invention is to provide an antipick device for alock which prevents a direct line of sight access to the key slot.

Another object of the invention is to provide an antipick device for alock which provides a means of protection for the lock against picking,drilling, punching, and cylinder pulling.

Various other objects of the invention in addition to those set forthabove will become apparent to those skilled in the art from thefollowing description, taken in connection with the accompanyingdrawings, wherein:

FIG. 1 is an exploded perspective view of a device constructed inaccordance with the invention;

FIG. 2 is a full cross sectional view of the device of FIG. 1, showninstalled with a lock in a panel;

FIG. 3 is a view similar to FIG. 2 illustrating the position of thedevice of the invention when a key is inserted in the lock;

FIG. 4 is a full cross sectional view of an alternative embodiment ofthe invention in the installed position;

FIG. 5 is a cross sectional view of a further alternative embodiment ofthe invention in the installed position;

FIG. 6 is a partial sectional view taken along lines 6--6 of FIG. 5 inthe direction of the arrows;

FIG. 7 is an elevational view of a specially designed key which may beadvantageously used in conjunction with the device of the invention;

FIG. 8 is an end view of an alternative key holder construction whichmay be employed in the device of the invention for use with the key ofFIG. 7; and

FIG. 9 is a sectional view of the key holder taken along line 9-9 ofFIG. 8 in the direction of the arrows.

Very generally, the anti-pick device of the invention comprises asecurity housing 11 adapted for mounting about the entrance to the slot12 of a lock 13. A key holder 14 is mounted slidably in relation to thehousing for linear movement along a path aligned with the key slot. Thekey holder has a recess 15 therein for receiving a key 16 and supportingthe key in alignment with the key slot. The recess extends transverselyof the path of movement of the key holder.

Referring now more particularly to FIGS. 1 and 2, the device of theinvention in accordance with the illustrated embodiment may be morereadily understood. The lock itself has a front flange 21 and agenerally cylindrical body extending from behind the flange. Oppositesides of the body 23 are provided with flats 25 thereon to prevent thelock from turning in the hole in the panel in which the lock is mounted.The hole in the panel in which the lock is mounted is provided with acorrespondingly out-of-round opening to mate with the flats and thusprevent rotation.

The lock 13 may be constructed internally of any suitable design, and inthe illustrated embodiment, the lock 13 is provided with an internalcylinder, not shown, which, when turned, rotates a generally square stud27 mounted at the back end of the lock. As shown in FIG. 2, the stud 27may pass through a correspondingly shaped hole in a lock cam 29, and maybe secured therein by means of a suitable bolt 31.

As is known in the art, the lock 13 is provided with a key slot 12therein into which a key 16 may be inserted. When the key is of theproper configuration, the internal cylinder, not shown, in the lock maybe rotated, to thus rotate the stud 27 and hence move the lock cam 29appropriately. The lock cam 29 may bear against any suitable block,panel, or latch plate, to provide locking action, as is known in theart.

The housing or body 11 is generally cylindrical in shape, having outerand inner cylindrical surfaces. An annular recess 35 is provided at oneend of the housing 11, thus providing an enlarging step in the internaldiameter of the body 11. As may be seen in FIG. 2, the opposite end ofthe housing or body 1 1 is provided with an annular flange 37 whichextends inwardly.

An outer retaining ring 41 is provided having an outer diameter matchingthe diameter of the recess 35 so that the outer retaining ring 41 willfit in the recess 35 as shown in FIG. 2. A pair of holes 43 are providedin the outer retaining ring 41 which are in alignment with a pair ofthreaded holes 45 in the housing 1 l at the bottom of the recess 35. Inthis matter, the outer retaining ring may be secured in the recess 35 bymeans of screws 47 (FIG. 2).

As may be seen in FIG. 2, the outer retaining ring 41 is provided withan annular recess 51 therein, the diameter of which is equal to theinner diameter of the housing 11. An inner retaining ring 53 is providedwith an outwardly projecting flange 55 which fits within the annularrecess 51 in the outer retaining ring 41.

The panel 57 in which the lock 13 is mounted may be any wall, door orsimilar structure. The inner diameter of the inner retaining ring 53 ismade such as to be less than the outer diameter of the flange 21 on thelock 3 13. In this manner, the inner retaining ring 53 may be clampedagainst the panel 57 between the flange 21 and a lock retainer nut 59threaded on the threaded body 23 of the lock 13. The flange 55 of theinner retaining ring retains the outer retaining ring 41 between it andthe panel 57 and thereby secures the housing 11 over the key slotentrance 12 of the lock 13.

As previously mentioned, the key holder 14 is mounted slidably in thehousing 11 for movement along a path aligned with the key slot 12. Tothis end, the key holder 14, which in the illustrated embodiment isgenerally cylindrical, is provided with an annular flange 61 whichprojects radially outward at one end of the key holder and which has anouter surface of a diameter equal to and mating with the inner surfaceof the housing 1 1. The outer diameter of the cylindrical key holder 14is slightly less than the inner diameter of the inwardly projectingflange 37 on the housing 11. Thus,

the key holder 14 is mounted in and guided within the housing 11, butmay not be pulled out of the housing.

The key holder 14 is provided with a recess 15 therein for receiving thekey 33 for supporting same in alignment with the key slot. in theillustrated embodiment, this recess comprises a slot which extends alongthe axis of the cylindrical key holder to the end thereof disposedinteriorly of the housing 11. The slot does not extend to the oppositeend of the key holder 14, and thereby leaves a wall 65 which extendstransversely to the path of movement of the key holder 14.

In the illustrated embodiment, a small hole 67 is provided at the baseof the recess 15, and the key is provided with a stud 69 thereon whichmates within the the key holder 14, the key holder is also rotated untilthe key llofindsand enters the keyway or slot 1 2 of the i lock 13. Thekey is then pushed into the lockby further slot 12 in the lock 13, andbecause the key holder 14 v fills up the opening in the housing 11, theonly external access to the lock is through the recess 15. Since therecess 15 does not extend through the entire length of the key holder14, but rather extends transversely of the path of movement of the keyholder, 21 direct line of sight into the lock is prevented. Accordingly,a conventional lock picking tool cannot be used to pick the lock, andany picking attempt by the utilization of other tools must be blind. Theexternal parts of the device of the invention are preferably hardened toresist cutting and drilling. By makingthe inner diameters of the outerretainer ring 41 larger than the outer diameters of the inner retainerring 53, any torque applied to the housing merely rotatesthe housingabout the lock- Accordingly, the lock cannot be removed by forcing it orunthreading it from the retainer nut 59.

An alternative embodiment of the invention is illustrated in FIG. 4. InFIG. 4, thoseelements of the device and associated structure which havefunction and dement of FIG. 4, the housing 111 is secured directly tothe panel 157 by means of screws 147 which enter directlyinto thehousing. This design eliminates the need hole to aid in retaining thekey in position with respect to the key holder 14. Also in theillustrated embodiment the key 16 is provided with an L-shaped extension71 thereon to facilitate inserting the key into and removing the keyfrom the recess 15 in the key holder 14..

Since the key holder 14 is free to rotate with respect to the key slot12 in the lock 13, and since the breadth of the recess 15 is selected toproperly align the key 16 with the key slot entrance, the key holder maybe I moved linearly to cause the key to enter the key slot, and may thenbe turned to cause the key to turn the internal cylinder within the lock13 and open the lock.

FIG. 3 shows the key inserted in the lock with the key holder in itsinnermost position.

In assembling the device of the invention, the key holder is insertedinto the body 11 so that the barrel of secured therein by the screws 47.The lock is then inserted into the hole in the panel 57 and securedtherein by the retainer nut 59. The housing assembly is thus securedover the entrance to the slot 12.

In operating the device of the invention, the key holder 14 is pulledout from thehousing 11 as far as possible, i.e., the position shown inFIG. 2. The key is then inserted in the recess 15 with the stud 69projecting downwardly into the hole 67 at the bottom of the slot. Thekey holder 14, with the key placed therein, is then pushed inwardly.While maintaining pressure on for the inner and outer retaining ringsbecause the housingis secured to the panel independently of the lock.

Additionally, an optional blocking means 148 is schematicallyillustrated in FIG. 4%.for normally covering the key slot of lock 113,but beingmovable relative to the 7 key slot to permit access thereto forinsertion of the key 1 16. This. provides an additional measure ofsecurity against blind picking of the lock through the use of perhaps amore sophisticated or specially designed picking .tool. Blocking means148 may comprise any through the urging or contact with the inner end ofthe key as the key is axially moved toward the key slot. This positionin response to the movement of the key holder i 114 relative to the keyslot by anysuitable camming arrangement or linkage between the keyholder and the shutter as indicated by broken line 150. In thisembodiment, axial movement of the key holder to its closed or keyengaged position (as shown, for example, in FIG. 3) is required to movethe blocking means 148 to its open" or access position. Any mechanism ofsuitable size for translating the linear movement of the key holder toangular movement of the shutter may be :em-

ployed.

Asa further alternative, the lock itself may be mounted to a panel,housing or bracket which is behind a second panel, serving asthe mainpanelor door. The 2 second panel may have a hole therein foraccommodating and. guiding the key holder. Accordingly, in thissituation the second panel comprises the security housing, and the needfor a closed cylindrical type of security housing as has beenhereinbefore described may be eliminated.

More particularly, reference is made to FIG. 5 which shows a furtheralternative embodiment, with those elements of the device and associatedstructure having function and design similar to the elements of theembodiment of FIGS. 1 to 3 given like reference numerals, preceded by a2. As can be seen, the panel 257, together with the housing body 211,forms the security housing, since the panel 257 blocks access to the keyslot of the lock 213 except through the opening 252 in the panel. Thebody 211 serves to support the lock 213 in fixed mounted relation to thepanel and to the opening 252 therein. The body 211 may be fastened tothe back or interior side of the panel 257 by means of screws 247inserted through ears 254 formed integrally with the body. As shown, thekey holder 214 has a flange 261 which nests within a counterbore at theback of the panel or door 257 when the key holder is in its open orextended position.

Blocking means 248 may be optionally included, and is shown to comprisea pair of separable metal vanes 258a and 258b (FIG. 6) which arerespectively pivot mounted at 262a and 2621; for angular motion as shownby the arrows. Each point is located so that the center of mass of thevanes causes them to normally swing together in the closed positionshown in FIG. 6 under the force of gravity. An inward bevel may beprovided along the respective inner edges 264a and 264b of the vanes sothat they will readily separate when contacted by the innerend of thekey 216 as it is urged forwardly toward the key slot. The parting lineof the vanes, being aligned with the key slot, will open and permitentry of the key when the key holder 214 has been rotated to the properangular orientation.

Of course, other mechanisms, employing springs, etc., may be utilizedfor the blocking means of the embodiment of FIG. 5, as well as of theembodiment of FIG. 4. Also, any such means may be employed with theembodiment of FIGS. 1 to 3, if desired. It is understood that the keyslot may be of a shape other than flat or straight such as circular orother special configurations.

FIG. 7 shows an alternative key design which may be used with themodified key holder construction of FIGS. 8 and 9. The key 16 has astraight tumbler engaging portion 302 along an axis 304 defined therebyfor insertion into a key slot of a lock, as previously described. A tangor gripping portion 306 is joined to the straight key portion 302 by astem 308 having a curved bearing surface 310 extending from one side ofthe axis 304 to the other.

The key holder 14' is similar to that hereinbefore described, exceptthat the recess 63' has a key supporting wall 312 forming a curvedsurface extending from an external point 314 furthest from the key slotto an external point 316 on the face of the key holder closest to thekey slot, and from one side of its longitudinal axis 318 to the other.The curvature of the supporting wall 312 mates with the complementarybearing surface 310 of the key 16, and the key nests securely within therecess 63' in proper alignment with the key slot for easy insertion andremoval.

With the key placed within the key holder, the tang 306 hooks over therearward end 320 of the key holder so that the straight surface 322abuts flush against end 320. A hole 324 is provided within the tang 306for key chain convenience. Of course, portions of the mating bearing andsupporting surfaces may be straight or approximately straight in somecircumstances, but generally less advantageously.

It may therefore be seen that the invention provides an improvedanti-pick device for a lock having a key slot. The device provides ameans of protection for the lock against picking, drilling, punching,cylinder pulling, and many other types of nefarious activities. Thedevice of the invention is relatively simple of construction, is easilyinstalled, and represents a significant improvement over the known priorart.

Various modifications of the invention in addition to those shown anddescribed herein will become apparent to those skilled in the art, fromthe foregoing description and accompanying drawings. Such modificationsare intended to fall within the scope of the appended claims.

What is claimed is:

1. A key for use with a lock of the type having a key holder disposedahead of the key slot and a key receiving recess in the holder having acurved key supporting wall extending from an outer periphery of theholder to a location adjacent the key slot, said key having:

a. a straight tumbler engaging portion along a straight axis forinsertion into the key slot of the lock, said tumbler engaging portionbeing disposed on at least one edge surface of said key, spaced from,but generally parallel to, said straight axis,

b. a gripping portion,

c. a stem joining the gripping portion to said tumbler engaging portion,said stem having a curved bearing surface generally complementary to thecurved supporting wall of the holder to facilitate sliding insertion ofthe key into the key slot, and

d. an edge located generally between said gripping portion and said stemand extending generally transverse to said axis so as to contact an endsurface of said key holder when the key is inserted therein.

2. A key as defined in claim 1 including a lateral portion locatedbetween said curved surface and said transverse edge, said lateralportion being adapted to contact a cooperatively shaped portion near theend surface of said key holder to prevent radially inward pivotalmovement of said key relative to said key holder when said key isinserted in said key slot.

UNETEB STATES PATENT GFFICE CETIFEQATE 0F (IURERECTION PATENT-N6. 2 702DATED May 13, 1975 iNVENTORk'S) Max Wiczer rr is certified that errorappears in the ab0veidenhfred parent and that said Letters Patent arehereby co rected as shown below:

Title sheet, Item 62, the filing date of the parent application Column3, line 56, place' should be -placed-.

En'gncd and Scaled this sixteenth Day of September 1975 [SEAL] Attesz:

C. MARSHALL DANN (mnmissr'nner uj'Parenls and Trademarks RUTH C. MASONArresting Officer

1. A key for use with a lock of the type having a key holder disposedahead of the key slot and a key receiving recess in the holder having acurved key supporting wall extending from an outer periphery of theholder to a location adjacent the key slot, said key having: a. astraight tumbler engaging portion along a straight axis for insertioninto the key slot of the lock, said tumbler engaging portion beingdisposed on at least one edge surface of said key, spaced from, butgenerally parallel to, said straight axis, b. a gripping portion, c. astem joining the gripping portion to said tumbler engaging portion, saidstem having a curved bearing surface generally complementary to thecurved supporting wall of the holder to facilitate sliding insertion ofthe key into the key slot, and d. an edge located generally between saidgripping portion and said stem and extending generally transverse tosaid axis so as to contact an end surface of said key holder when thekey is inserted therein.
 2. A key as defined in claim 1 including alateral portion located between said curved surface and said transverseedge, said lateral portion being adapted to contact a cooperativelyshaped portion near the end surface of said key holder to preventradially inward pivotal movement of said key relative to said key holderwhen said key is inserted in said key slot.